The police surrounded a Saudi Arabian Airlines flight at Manila airport on Tuesday after reports said it was "under threat", with passengers not allowed to disembark, the aviation authority spokesman said.

"A Saudi plane has been isolated at the airport runway," Civil Aviation Authority of the Philippines spokesman Eric Apolonio said.

The Saudi plane isolated after a false alarm. Screenshot from YouTube video

However, it later turned out to be a "false alarm", an airline spokesman told AFP.

There was a "false alarm for hijack for Flight 872," the spokesman said in the Saudi capital Riyadh.

Philippine airport officials said that Saudia Airlines plane mistakenly sent a distress call before landing at Manila's airport. The passengers have now been allowed to disembark, reported AP.

The airport had earlier said in a statement that it had received information of the threat, which it did not describe, when Flight SV872 was 30 miles (48 kilometres) away from landing.

It had said the Boeing aircraft was moved to a designated isolation area after it landed.

TV stations had shown the plane parked near a ramp with people standing nearby, while normal airport operations continued elsewhere.